St. Paul in the sixth chapter of his letter to the Ephesian counsels us to put on the Armor of God. He then goes on to list each piece of armor. At first it may appear to simply be a list but there is a real order which follows in a very specific way christian life. Their are six parts of the armor; belt, breastplate, footwear, shield, helmet, and sword.
First is the belt, having girded your loins with Truth. The loins represent our bodily appetites, and most literally our sexual appetites. Sexual sins are quite easy to fall into yet they can be very easily hidden. Masturbation, pornography, contraception and most others short of public displays and orgies are private with the effects only directly affecting oneself and one's spouse. Paul doesn't say to eliminatethe loin but simply to gird the loin with truth. I'll come back to this as foundational after I have spoke on the others.
Having put on the Breastplate of Righteousness. The Breastplate relates to our public conduct. This is where the life of virtue is put to the test. It is the righteous man who acts prudently (not prudishly) in the world. He is just in his dealings with his fellow man and conducts his affairs with dignity and honour. Slow to anger, but flashing with a righteous anger in the face of injustice.
Having shod your feet with the equipment of the Gospel of Peace. It is the gospel than, that moves the feet. Our action and progress through the world is order toward the proclamation of the gospel. It is the furthering of that gospel that compels us to act rightly. The gospel then is the reason for our right action.
Taking the Shield of faith, with which you can quench all the flaming darts of the evil one. When we preach the gospel the devil attacks us to beat us back into silent submission. It is our faith that guards against his flaming darts. We preach Christ and him crucified a stumbling block to the Jews and scandal to the Gentiles. It is faith in him crucified that encourages us to continue on.
Take the helmet of salvation. When we resist satan he changes tactics and one of his most powerful attacks is against our intellect. There are many intellectual faults, the one I will suggest here is Intellectual pride. We are tempted to think, "look at this great knowledge I have come to. Look at how well I can articulate the gospel and how many hear and believe what I say." Thus we distance ourself from Christ. But salvation is the guard against such thoughts. I myself have the same need of salvation that every other man has. My thoughts, my insight are all only gifts from God and even my very intellect is a gift resulting from how God knit me together in my mothers womb.
The Sword of the Spirit, which is the word of God. Et verbum caro factum est, St. John tells us in the prologue to his gospel. The Sword that we wield is quiet literally Jesus himself. Jesus is the word of God whom we call on to fight against the powers, the principalities, the world rulers of this present darkness, and the spiritual hosts of wickedness in the heavenly places.
Let's return the loins girded with truth. We have seen how fundamental and foundational this first garment is with the recent priest scandals relating to child abuse. These priests had the other five parts of armor. They celebrated Mass, making the sword of the spirit present in the Eucharist. They had on the helmet of salvation to defend against intellectual pride. They had faith to defend them against the spiritual snares of the devil. They were moved to preach the gospel. They had a breastplate of good works and virtues in the public eye. All this they had but they did not first gird themselves with truth and even though this was a private sin, when sin of sexual abuse came into the light, it showed that they had failed to protect the first and most intimate manhood. Without truth protecting their manhood all satan had to do to make all their other works infertile was to attack their manhood. And we see that all those things that should have been good works for the building of the kingdom, because of this infertility actually harmed the kingdom they claimed to be helping.